Histoloical and Biochemichal Study on the Toxic Effects of Bisphenol A on the Thyroid Gland of Adult Male Albino Rats and the Possible Protection by Selenium

Abstract

Background:The worldwide used bisphenol A (BPA) which is incorporated in many plastic industries is considered as an endocrine disruptor. Warnings raised by many agencies against the excessive use of such substances because of its confirmed hazardous effects. Selenium (Se) is known to have antioxidant role in living systems. Aim of the work:The aim of the current study was to evaluate the extent to which BPA can affect the thyroid gland structure and function and if there is any protective role for selenium. Material and Methods: Twenty four adult male rats divided equally into three groups. Group I as a control, group II included rats that received 50 mg/kg/ day bisphenol orally for eight weeks and group III that received bisphenol in the same dose for the same duration concomitantly with selenium in a dose of 0.5 mg/kg. At the end of the experiment, blood samples were taken for hormonal essay and statistical analysis. Thyroid gland tissue samples were processed for histological and immunohistochemical study. Results: BPA-treated rats showed degenerative changes in the form of decreased or absent colloid and fusion of the follicles. Other follicles showed signs of hyperactivity as microfollicles, follicular epithelial cell stratification and many lysosomes. Strong positive inducible nitric oxide synthase immunoreactivity and highly significant increase of serum TSH with decreased T3 and T4 were recorded. BPA+selenium treated group revealed nearly normal appearance of thyroid gland architecture. Conclusion: BPA had deleterious effects on thyroid structure and function. Concomitant administration of selenium preserved to a great extent the thyroid gland architecture.

Ameliorative Impacts of Dactyloctenium aegyptium and Parapholis incurva Ethanolic Extracts on Sodium Fluoride Induced Pathological Alterations in the Thyroid Gland in Male Rats

“…This could be related to severe inflammation in the thyroid gland, which causes vasoconstriction and blood vessel congestion. Such findings coincide with that of other studies [42][43]. Furthermore, the current investigation revealed small sized empty follicles with damaged basement membranes and lumina fusion.…”

“…Some follicular lumina of NaFtreated group showed desquamated follicular cells. In accordance, some researchers reported that sloughing of degenerated follicular epithelial cells is possible [43]. The histological alterations of the rat thyroid gland following NaF treatment can be due to the increased TSH level.…”

Effect of Metalaxyl on the thyroid gland in adult female albino rats and the possible protective role of ginger (Histological and immunohistochemical study)

“…Evidence of hyperactivity was found in C cells such as follicular cells. These findings were also in agreement with Mohamed and Rateb [44] who reported that a hyperactive thyroid showed the presence of enlarged C cells distributed either in small groups or even singly. Some authors [45] attributed that to the high level of TSH, leading to hyperplasia and hypertrophy of C cells.…”